Systems and methods for composite gun barrel

ABSTRACT

A composite gun barrel comprising an elongated cylinder with a carbon fiber coating. The coating comprises one or more of a stiffening layer, a strengthening layer, and a heat transfer layer. The stiffening layer comprises plies of ultra-high modulus carbon fiber oriented in a unidirectional configuration along a longest axis of the elongated cylinder. The strengthening layer comprises carbon fibers oriented in a unidirectional configuration perpendicular to the stiffening layer. The heat transfer layer comprises carbon fiber oriented in a unidirectional configuration at about a 45° angle to the stiffening layer.

BACKGROUND

The present application relates to systems and methods for a composite gun barrel comprising a carbon fiber coating with a stiffening layer comprising ultra-high modulus carbon fiber polymer, a strengthening layer of carbon fiber polymer, and a heat transfer layer of carbon fiber polymer, the layers configured to stiffen the composite gun barrel, dampen vibration, and facilitate heat transfer.

Conventional ultra-high modulus carbon fiber polymer products are costly and difficult to work and have found very limited application. This is due in part to the fact that as the modulus of carbon fiber increases, the ability to bind individual carbon fibers to each other decreases. Conventional ultra-high modulus carbon fiber polymers exhibit poor short beam shear test results and consequently have found limited use in industry. However, the present application describes methods and systems for utilizing ultra-high modulus carbon fiber polymers in composite gun barrels.

Carbon fibers polymers exhibit low weight, low thermal expansion, and high strength. Strength is defined as the amount of force that can be applied to material before it fails. Stiffness is defined as the amount that a material can deform when a given force is applied and is defined by Young's Modulus. High modulus carbon fibers possess high stiffness, but low strength and can break with less force than lower modulus carbon fibers. Likewise, lower modulus carbon fibers possess high strength, but low stiffness. Also higher modulus carbon fibers cost much more than lower modulus fibers. In some cases higher modulus carbon fibers can cost over 10 times more than their lower modulus counterparts.

Carbon fibers can be selected and assembled based on their unique properties to enhance a composite gun barrel's desired properties. When engineering a composite gun barrel, factors such as weight, strength, stiffness, thermal expansion, thermal conductivity, vibration reduction, vibration dampening, and cost affect the selection of the carbon fiber. While a stiff fiber (lower modulus) resists bending, a strong fiber (higher modulus) resists breaking Furthermore, the cost of the selected carbon fiber must be taken into account as part of the overall production cost. Unfortunately, different areas of the composite gun barrel require different characteristics. For example, a chamber of the composite gun barrel experiences different forces in different planes than a chase or a muzzle. Different sections of the composite gun barrel require different levels of stiffness or strength.

Additionally, conventional woven carbon fiber sheets as known in the art possess high strength but suffer from low stiffness. Conventional composite gun barrels comprise coatings of conventional woven carbon fiber that exhibit lighter weight and higher strength, but do not possess high stiffness.

BRIEF SUMMARY

In some embodiments, the systems and methods of the present application describe a composite gun barrel coating comprising a stiffening layer of carbon fiber polymer bonded to an elongated cylinder. The stiffening layer can comprise high modulus carbon fibers oriented in a first unidirectional configuration. The first unidirectional configuration can be oriented about parallel to a longest axis of the elongated cylinder. In other embodiments, the carbon fibers can comprise a modulus of greater than about 3,400 MPa. In yet other embodiments, the carbon fibers can comprise a modulus of greater than about 9,000 MPa. In some embodiments, the stiffening layer can comprises at least six plies of carbon fibers. In other embodiments, the stiffening layer can comprise a thickness of about 0.06 inches. In yet other embodiments, the coating can further comprise a strengthening layer. The strengthening layer can comprise a carbon fiber polymer with carbon fibers oriented in a second unidirectional configuration. The second unidirectional configuration can be oriented about perpendicular to a longest axis of the elongated cylinder. In some embodiments, the strengthening layer can comprise a modulus less than the modulus of the stiffening layer. In other embodiments, the coating can further comprise a heat transfer layer. The heat transfer layer can comprise a carbon fiber polymer with carbon fibers oriented in a third unidirectional configuration. The third unidirectional configuration can be oriented between about parallel and about perpendicular to the first unidirectional configuration. In other embodiments, the heat transfer layer can be configured to transfer heat from the coating.

In some embodiments, the systems and methods of the present application describe a composite gun barrel coating comprising a stiffening layer of carbon fiber polymer comprising high modulus carbon fibers oriented in a first unidirectional configuration a strengthening layer of carbon fiber polymer comprising carbon fibers oriented in a second unidirectional configuration, the second unidirectional configuration oriented about perpendicular to the first unidirectional configuration and a heat transfer layer of carbon fiber polymer with carbon fibers oriented in a third unidirectional configuration, the third unidirectional configuration oriented between parallel and perpendicular to the first unidirectional configuration. In other embodiments, the stiffening layer can comprise a modulus of greater than about 9,000 MPa. In yet other embodiments, the strengthening layer can comprise a modulus less than a modulus of the stiffening layer. In some embodiments, the heat transfer layer can comprises a modulus less than a modulus of the stiffening layer and greater than a modulus of the strengthening layer. In some embodiments, the stiffening layer can be bonded to an elongated cylinder, the strengthening layer can be bonded to the stiffening layer, and the heat transfer layer can be bonded to the strengthening layer.

In some embodiments, the systems and methods of the present application describe a composite gun barrel comprising an elongated cylinder comprising a chamber at a proximal end and a muzzle at a distal end, the elongated cylinder further comprising a bore traversing the elongated cylinder from the chamber to the muzzle, and a carbon fiber coating comprising a stiffening layer bonded to the elongated cylinder, a strengthening layer bonded to the stiffening layer, and a heat transfer layer bonded to the strengthening layer. The stiffening layer can comprise ultra-high modulus carbon fibers oriented in a first unidirectional configuration, the first unidirectional configuration oriented parallel to a longest axis of the elongated cylinder. The strengthening layer can comprise carbon fibers oriented in a second unidirectional configuration, the second unidirectional configuration oriented about perpendicular to the first unidirectional configuration. The heat transfer layer can comprise carbon fibers oriented in a third unidirectional configuration, the third unidirectional configuration oriented between parallel and perpendicular to the first unidirectional configuration. In other embodiments, the stiffening layer can comprises a modulus greater than about 9,000 MPa. In yet other embodiments, one or more of the stiffening layer, the strengthening layer, and the heat transfer layer can extend at least in part from the chamber to the muzzle. In some embodiments, one or more of the stiffening layer, the strengthening layer, and the heat transfer layer can comprise multiple plies of carbon fiber. In other embodiments, one or more of the stiffening layer, the strengthening layer, and the heat transfer layer can comprise multiple plies of carbon fiber configured with more plies laid at the muzzle than at the chamber. In yet other embodiments, one or more of the stiffening layer, the strengthening layer, and the heat transfer layer can comprise multiple plies of carbon fiber configured with more plies laid at the chamber than at the muzzle.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the manner in which the above recited and other features and advantages of the present application are obtained, a more particular description of some aspects will be rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. Understanding that the drawings depict only typical embodiments of the present application and are not, therefore, to be considered as limiting the scope of the application, the present application will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1A illustrates some embodiments of a side view of a composite gun barrel;

FIG. 1B illustrates some embodiments of a cut-away side view of a composite gun barrel;

FIG. 1C illustrates some embodiments of a side view of an elongated cylinder;

FIG. 1D illustrates some embodiments of a cut-away side view of an elongated cylinder;

FIG. 2A illustrates some embodiments of a side view of a stiffening layer;

FIG. 2B illustrates some embodiments of a side view of a strengthening layer;

FIG. 2C illustrates some embodiments of a side view of a heat transfer layer.

DETAILED DESCRIPTION

It will be readily understood that the components of the present application, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the system and method of the present application is not intended to limit the scope of the application, as claimed, but is merely representative of the presently preferred embodiments of the application.

The present application describes systems and methods comprising a composite gun barrel. In some embodiments, a composite gun barrel can comprise an elongated cylinder coated with a plurality of carbon fiber layers. A composite gun barrel can be configured to reduce vibration, improve heat exchange, improve accuracy, and reduce weight. The systems and methods can comprise a composite gun barrel configured as part of a firearm such as a carbine, a hunting rifle, an assault rifle, a sniper rifle or any other similar rifle. In other instances, the systems and methods can comprise a composite gun barrel for any type of personal firearm such as a handgun, pistol, rifle, shotgun, or any other type of firearm. A composite gun barrel can also be employed with larger weapons that employ a gun barrel such as vehicle or aircraft mounted weapons systems.

FIG. 1A illustrates a side view of some embodiments of a composite gun barrel 10. In some embodiments, composite gun barrel 10 can comprise an elongated cylinder 20 coated at least in part by a carbon fiber coating 30. The elongated cylinder 20 can be configured to run the length of the composite gun barrel 10. In some embodiments, the carbon fiber coating 30 can be configured to coat the entire length of the elongated cylinder 20. In other embodiments, the carbon fiber coating 30 can be configured to coat less than the entire length of the composite gun barrel 10. FIG. 1B illustrates a cut-away side view of a composite gun barrel 10. The elongated cylinder 20 can be configured to run the entire length of the composite gun barrel 10. The carbon fiber coating 30 can be configured to coat less than the entire length of the composite gun barrel 10. The elongated cylinder 20 can be configured with a bore 28. The bore 28 can be configured to allow a bullet, once fired, to travel from an action of a firearm through the composite gun barrel 10 via the bore 28 and exit the composite gun barrel 10 towards a desired target. In some embodiments, the bore 28 can comprise rifling such as land and groove rifling or polygonal rifling. The bore 28 can comprise many different configurations as is well known in the art.

FIGS. 1C and 1D illustrate some embodiments of elongated cylinder 20. FIG. 1C illustrates a side view of some embodiments of elongated cylinder 20 and FIG. 1D illustrates some embodiments of a cut-away side view of elongated cylinder 20. Elongated cylinder 20 can comprise a muzzle 22 disposed at a distal end of the elongated cylinder 20 and a chamber 24 disposed at a proximal end of the elongated cylinder 20. Elongated cylinder 20 can further comprise a chase 26 disposed between the muzzle 22 and the chamber 24. Elongated cylinder 20 can also comprise a bore 28 as described above.

In some embodiments, elongated cylinder 20 may comprise steel, titanium, stainless steel, alloys of steel, alloys of metals, ceramic or other suitable material. In other embodiments, elongated cylinder 20 can be configured from any material known in the art that possess the properties to withstand high temperatures, caustic gasses and contact with metals traveling at high velocities. In yet other embodiments, elongated cylinder 20 can comprise 416R stainless steel. In some embodiments, elongated cylinder 20 can comprise 4140 chrome moly steel.

In some embodiments elongated cylinder 20 can be manufactured from a section of steel barrel stock. The section of steel barrel stock can be drilled, reamed, rifled, and lapped to form the bore 28. In other embodiments, the section of steel barrel can then be turned down to a desired dimension with desired wall thickness. In some embodiments, the section of steel barrel can be turned down on a lathe or similar tool to remove an outer portion of the chase 26 to accommodate the carbon fiber coating 30. In other embodiments, the section of steel barrel can be turned down in other configurations such as leaving a portion of material that is not turned down at the muzzle 22 and/or leaving a portion of material that is not turned down at the chamber 24. In yet other embodiments, a portion of material that is not turned down at the chamber 24 can be tapered to meet the turned down portion at the chase 26.

In addition, an outer surface of the elongated cylinder 20 may comprise a coating, such as a diamond-like coating or diamond-like carbon (“DLC”) that can be bonded to the elongated cylinder 20. In some embodiments, DLC can comprise amorphous carbon material that displays some of the typical properties of diamond. In other embodiments, the DLC can be bonded to the entire surface of elongated cylinder 20. The yet other embodiments, the DLC can be applied to an outer surface of elongated cylinder 20. In some embodiments, the DLC may be applied to machined portions of the elongated cylinder 20.

In some embodiments, the elongated cylinder 20 may comprise a single material construction. In other embodiments, elongated cylinder 20 may comprise a more than one material. For example the chamber 24 can be formed from a first material and/or a slide cylinder can be formed from a second material. Likewise, the chase 26, the muzzle 22, and a bell can be formed from the same or distinct materials. In yet other embodiments, a bell can be formed from one material and the muzzle 22 can be formed from another material. In some embodiments, the chamber 24 may comprise a first material and the chase 26 may comprise a second material. In other embodiments, components of the elongated cylinder 20 can comprise alternating materials and/or unique materials or any combination thereof. In yet other embodiments, the elongated cylinder 20 can comprise additional components, structures, and/or configurations. For example, elongated cylinder 20 can comprise additional apparatus attached to the muzzle 22, such as a noise suppressor, flash suppressor, muzzle brake, bayonet mount, sighting device, and any other apparatus known in the art. In some embodiments, elongated cylinder 20 can further comprise a heat sink configured to receive heat from at least a portion of the elongated cylinder 20.

As described above, composite gun barrel 10 can comprise a carbon fiber coating 30. In some embodiments, carbon fiber coating 30 can comprise one or more of carbon fiber-reinforced polymer, carbon fiber-reinforced plastic or carbon fiber-reinforced thermoplastic. In other embodiments, carbon fiber coating 30 comprises a matrix and a reinforcement. In yet other embodiments, the matrix comprises one or more resins such as a thermoset resin, an epoxy, a thermoplastic polymer, a polyester, and/or a vinyl ester. In some embodiments, the reinforcement comprises carbon fibers. In other embodiments, the reinforcement comprises other types of fibers. In yet other embodiments, the reinforcement comprises one or more of carbon fiber, aramid fibers, Kevlar® fibers, Twaron® fibers, aluminum fibers, ultra-high-molecular-weight polyethylene (UHMWPE) fibers, and/or glass fibers. In some embodiments, carbon fiber coating 30 can comprise other additives such as silica, rubber, and/or carbon nanotubes.

In some embodiments, the carbon fiber coating 30 can comprise carbon fiber produced from a precursor polymer such as petroleum pitch, rayon, and/or polyacrylnitrile (PAN). The precursor polymer can be spun into filament yarns using chemical and mechanical processes to align the polymer atoms to enhance the physical properties of the carbon fiber. The filament yarns can then be heated to drive off the non-carbon atoms in a process known as carbonization to produce carbon fiber.

FIGS. 2A, 2B, and 2C illustrate some embodiments of carbon fiber coating 30. Carbon fiber coating 30 can comprise one or more layers. Individual layers can comprise one or more plies. A ply can comprise a single thickness of individual fibers. Carbon fiber coating 30 can comprise one or more of a stiffening layer 32, a strengthening layer 34, and/or a heat transfer layer 36. In FIGS. 2A, 2B, and 2C, the axis direction indicated by reference A runs parallel with the longest dimension of elongated cylinder 20. Reference B indicates an axis direction that is offset by an angle C from axis A. Therefore, for an axis direction B that is parallel to axis A, offset angle C would equal 0°. Likewise, for an axis direction B that is perpendicular to axis A, offset angle C would equal 90°. These same orientations are used below to describe various orientations of fibers within layers and plies of carbon fiber coating 30.

FIG. 2A illustrates some embodiments of a stiffening layer 32. In some embodiments, stiffening layer 32 can be bonded to elongated cylinder 20. In some embodiments, the stiffening layer 32 can be configured to stiffen the composite gun barrel 30. The stiffening layer 32 can also be configured to dampen vibration and facilitate heat transfer to a heat sink. In some embodiments, the stiffening layer 32 may comprise an ultra-high modulus carbon fiber. In other embodiments, the stiffening layer 32 can comprise pitch fibers and/or PAN fibers. In yet other embodiments, the stiffening layer 32 can comprise mesophase pitch fibers with a higher modulus, higher thermal conductivity, and different friction properties than conventional PAN fibers. In some embodiments, stiffening layer 32 may further comprise fibers pre-impregnated with resin. In other embodiments, fibers comprising stiffening layer 32 can comprise a higher modulus thereby reducing barrel vibration to result in more accurate shooting.

In some embodiments, stiffening layer 32 can comprise an ultra-high modulus carbon fiber polymer with a modulus of greater than about 3,400 MPa. In other embodiments, stiffening layer 32 can comprise an ultra-high modulus carbon fiber polymer with a modulus of greater than about 9,000 MPa. In yet other embodiments, stiffening layer 32 can comprise an ultra-high modulus carbon fiber polymer with a modulus of greater than about 2,000 MPa, 3,000 MPa, 3,400 MPa, 4,000 MPa, 5,000 MPa, 6,000 MPa, 7,000 MPa, 8,000 MPa, 9,000 MPa, 10,000 MPa, 11,000 MPa, or 12,000 MPa. In some embodiments, stiffening layer 32 can comprise a K63712 pitch-based fiber with a tensile modulus of about 92 Msi (640 GPa) and a tensile strength of about 380 Ksi (2,600 MPa).

In some embodiments, stiffening layer 32 may comprise a single ply of carbon fibers. In other embodiments, stiffening layer 32 may comprise one or more plies. In yet other embodiments, stiffening layer 32 can comprise 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, or more plies. In some embodiments, stiffening layer 32 can comprise six plies of carbon fibers comprising a stiffening layer thickness of approximately 60 thousandths of an inch (0.06 in.) or about 1524 microns. In other embodiments, stiffening layer 32 can comprise a stiffening layer thickness of about 0.01 inch, 0.02 inch, 0.03 inch, 0.04 inch, 0.05 inch, 0.06 inch, 0.07 inch, 0.08 inch, 0.09 inch, 0.10 inch, or greater.

Referring again to FIG. 2A, in some embodiments carbon fibers in stiffening layer 32 can be laid in a unidirectional configuration. In other embodiments, carbon fibers in stiffening layer 32 can be laid such that individual fibers within a ply are arranged such that the individual fibers are substantially parallel to one another. In other embodiments, carbon fibers in stiffening layer 32 can be laid in a unidirectional configuration parallel with axis A with an offset C of about 0°. In some embodiments, fibers of stiffening layer 32 can be laid in a unidirectional configuration with an offset C of less than 2°. In some embodiments, fibers of stiffening layer 32 can be laid in a unidirectional configuration with an offset C of less than 5°. In some embodiments, fibers of stiffening layer 32 can be laid in a unidirectional configuration with an offset C of less than 8°. In some embodiments, fibers of stiffening layer 32 can be laid in a unidirectional configuration with an offset C of less than 10°. In yet other embodiments, unidirectional application of fibers can be configured to stiffen the composite gun barrel 10 to optimize desired properties such as vibration dampening and heat transfer towards a heat sink such a flash suppressor or muzzle brake.

With continued reference to FIG. 2A, stiffening layer 32 can be bonded to elongated cylinder 20. In some embodiments, pre-impregnated carbon fiber material can be bonded to elongated cylinder 20 by threading pre-impregnated carbon fiber material onto elongate cylinder 20 and then curing the pre-impregnated resin to bond the carbon fiber material. In other embodiments, to improve the bond between the elongated cylinder 20 and the stiffening layer 32, a surface of the elongated cylinder 20 may be roughened before bonding the carbon fiber material.

In some embodiments, stiffening layer 32 can be bonded using epoxy. In other embodiments, individual plies of carbon fiber may be applied and bonded with resin one layer at a time. In yet other embodiments, a series of plies may be placed and then bonded with resin as a single layer. In some embodiments, the stiffening layer 32 can be bonded along the entire length of the elongated cylinder 20. In other embodiments, bonding the stiffening layer 32 to the elongated cylinder 20 over the entire length of the elongate cylinder 20 provides improved predictability of the vibration dampening and heat transfer properties.

In some embodiments, stiffening layer 32 can comprise plies applied to the elongated cylinder 20 in varying thicknesses at different points along the elongated cylinder 20. For example, a first ply can be placed to extend from the muzzle 22 to the chamber 24. A second ply can then be placed to extend from the muzzle 22 along the chase 26 to a distance shorter than the first ply. Subsequent plies can be laid in a similar fashion such that stiffening layer 32 comprises a greater number of plies at the muzzle 22 than at the chamber 24. Plies can also be laid in this manner to taper a thickness of the stiffening layer 32 from the muzzle 22 to the chamber 24 such that a thickness of the stiffening layer 32 tapers from a greater thickness at the muzzle 22 to a lesser thickness at the chamber 24. In some embodiments, the stiffening layer 32 can be configured by laying plies in this staggered or tapering pattern to dampen vibrations which may be more likely to arise at different locations along the elongated cylinder 20.

In some embodiments, the stiffening layer 32 can comprise plies applied in a reverse order as described above, with the greatest number of plies extending from the chamber 24 and the number of plies decreasing towards the muzzle 22. In other embodiments, a greater number of plies may be laid at a point between the muzzle 22 and the chamber 24. In yet other embodiments, plies may be laid in nodes along the elongated cylinder 20, increasing in thickness at specific intervals and decreasing in thickness between those intervals. In yet other embodiments, the layering of plies in the stiffening layer 32 can be configured to correspond to natural harmonics of the elongated cylinder and the plies may be layered in a thickness along the elongated cylinder 20 to maximize dampening of vibrations.

Referring now to FIG. 2B, in some embodiments, a strengthening layer 34 can be laid on top of the stiffening layer 32. In other embodiments, strengthening layer 34 can be configured to add strength to the composite gun barrel 10. In yet other embodiments, strengthening layer 34 can be configured to add strength to composite gun barrel 10 to increase an amount of force that can be applied before the composite gun barrel 10 fails. In some embodiments, strengthening layer 34 can comprise a carbon fiber polymer as described above. In other embodiments, strengthening layer 34 can be configured with carbon fibers comprising a modulus lower than the carbon fibers comprising the stiffening layer 32.

In some embodiments, strengthening layer 34 can comprise one or more plies containing fibers oriented in a unidirectional configuration. In other configurations, strengthening layer 34 can comprise fibers oriented in a unidirectional configuration substantially perpendicular to axis A with an offset C of about 90°. In yet other embodiments, strengthening layer 34 can comprise fibers oriented in a unidirectional configuration with an offset C of between 70° and 90°. In yet other embodiments, strengthening layer 34 can comprise fibers oriented in a unidirectional configuration with an offset C of between 75° and 85°. In yet other embodiments, strengthening layer 34 can comprise fibers oriented in a unidirectional configuration with an offset C of between 70° and 110° and any subrange therein.

In some embodiments, the strengthening layer 34 can be configured to provide several mechanical advantages to the composite gun barrel 30. These mechanical advantages can include increased strength along a section of the elongated cylinder 20 over which strengthening layer 34 is laid. In other embodiments, these mechanical advantages can be attributed, in part, to carbon fiber's increased strength along its longest axis. In other embodiments, the strengthening layer 34 can be configured to take advantage of carbon fiber's increased strength along its longest axis by orienting unidirectional plies of fibers within the strengthening layer 34 in certain orientations.

For example, by orienting carbon fibers in a unidirectional configuration substantially perpendicular to axis A with an offset C of about 90°, the elongated cylinder 20 can be strengthened against forces created inside the bore 28 during firing of a bullet. Firing of a bullet triggers an explosion in the chamber 24 and bore 28 that exerts force along the bore 28 and the elongated cylinder 20. This force is known as bore force and exerts force against walls of the elongated cylinder 20. Accordingly, in some embodiments, strengthening layer 34 can be configured to reinforce areas along the elongated cylinder 20 that experience greater bore force, such as the chamber 24 and the muzzle 22. In other embodiments, strengthening layer 34 can be configured with plies laid in a staggered or tapered configuration as described above for stiffening layer 32. In yet other embodiments, strengthening layer 34 can be configured with varying number of plies in various locations to create nodes where the strengthening layer 34 comprises a greater number of plies to strengthen certain areas. In other embodiments, strengthening layer 34 can be configured to comprise plies extending from chamber 24 to muzzle 22.

In some embodiments, strengthening layer 34 may comprise a single ply of carbon fibers.

In other embodiments, strengthening layer 34 may comprise one or more plies. In yet other embodiments, strengthening layer 34 can comprise 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, or more plies. In some embodiments, strengthening layer 34 can comprise six plies of carbon fibers comprising a strengthening layer thickness of approximately 60 thousandths of an inch (0.06 in.) or about 1524 microns. In other embodiments, strengthening layer 34 can comprise a strengthening layer thickness of about 0.01 inch, 0.02 inch, 0.03 inch, 0.04 inch, 0.05 inch, 0.06 inch, 0.07 inch, 0.08 inch, 0.09 inch, 0.10 inch, or greater.

Referring now to FIG. 2C, in some embodiments, composite gun barrel 10 can further comprise a heat transfer layer 36. In other embodiments, heat transfer layer 36 can comprise any carbon fiber polymer as described above. In other embodiments, heat transfer layer 36 can be bonded onto strengthening layer 34. In yet other embodiments, heat transfer layer 36 can be configured to offset any reduction of heat transfer along axis A of the elongated cylinder 20 caused by any orientation of the carbon fibers in the strengthening layer 34 at a C offset of about 90°. In other embodiments, heat transfer layer 36 can be configured to facilitate heat transfer from stiffening layer 32 and strengthening layer 34 to ambient surroundings. In yet other embodiments, heat transfer layer 36 can be configured to facilitate heat removal from stiffening layer 32 and strengthening layer 34.

In some embodiments, heat transfer lay 36 can comprise one or more plies containing fibers oriented in a unidirectional configuration. In other configurations, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration at an angle to axis A with an offset C of about 45°. In yet other embodiments, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration with an offset C of between 30° and 60°. In yet other embodiments, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration with an offset C of between 40° and 50°. In yet other embodiments, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration with an offset C of between 30° and 60° and any subrange therein.

In some configurations, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration at an angle to axis A with an offset C of about 135°. In yet other embodiments, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration with an offset C of between 120° and 150°. In yet other embodiments, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration with an offset C of between 130° and 140°. In yet other embodiments, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration with an offset C of between 120° and 150° and any subrange therein. In some embodiments, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration with an offset C sufficient to form a left-handed helical twist on elongated cylinder 20. In other embodiments, heat transfer layer 36 can comprise fibers oriented in a unidirectional configuration with an offset C sufficient to form a right-handed helical twist on elongated cylinder 20.

In some embodiments, heat transfer layer 36 can be configured to be bonded to areas along the elongated cylinder 20 that experience greater heat, such as the chamber 24 and the muzzle 22. In other embodiments, heat transfer layer 36 can be configured with plies laid in a staggered or tapered configuration as described above for stiffening layer 32. In yet other embodiments, heat transfer layer 36 can be configured with varying number of plies in various locations to create nodes where the heat transfer layer 36 comprises a greater number of plies to facilitate heat transfer at certain areas. In other embodiments, heat transfer layer 36 can be configured to comprise plies extending from chamber 24 to muzzle 22.

In some embodiments, heat transfer layer 36 can comprise plies of woven carbon fiber strands woven in about a 45° angle. In other embodiments, heat transfer layer 36 can comprise fibers with a lower modulus than the stiffening layer 32. In yet other embodiments, heat transfer layer 36 can comprise fibers with a higher modulus than the strengthening layer 34. In some embodiments, the fiber orientation of the heat transfer layer 36 can be configured to provide many of the advantages of the stiffening layer 32 and the strengthening layer 34. In other embodiments, the heat transfer layer 36 can be configured to stiffen, strengthen, and transfer heat.

In some embodiments, stiffening layer 32, strengthening layer 34, and heat transfer layer 36 may be bonded onto elongated cylinder 20 in any order and in any combination. In other embodiments, composite gun barrel 10 can comprise one or more stiffening layers 32, one or more strengthening layers 34, and one or more heat transfer layers 36. As described above, individual layers can be configured to extend for the entire length of elongated cylinder 20 or for sections of elongated cylinder 20. In some aspects, individual layers can be configured in a staggered or tapered configuration. In yet other embodiments, composite gun barrel 10 can comprise one or more layers and one or more combinations of stiffening layer 32, strengthening layer 34, and/or heat transfer layer 36. In some embodiments stiffening layer(s) 32 can be configured to stiffen at least a portion of the elongated cylinder 20. In other embodiments, strengthening layer(s) 34 can be configured to strengthen at least a portion of the elongated cylinder 20. In yet other embodiments, heat transfer layer(s) 36 can be configured to facilitate heat transfer at least along a portion of elongated cylinder 20.

In some embodiments, the present application comprises systems and methods for manufacturing a composite gun barrel 10. In some embodiments, a method for manufacturing a composite gun barrel 10 can comprise providing a section of steel barrel stock. The section of steel barrel stock can be drilled, reamed, rifled, and lapped to form a bore 28. Next, the drilled, reamed, rifled, and lapped section of barrel stock can be turned down on a lathe or similar tool to remove an outer portion to produce an elongated cylinder 20. A carbon fiber coating 30 can then be bonded to the elongated cylinder 20.

The carbon fiber coating 30 can be bonded to the elongated cylinder 20 by bonding one or more of a stiffening layer 32, a strengthening layer 34, and/or a heat transfer layer 36. The stiffening layer can be bonded to the elongated cylinder 20 by bonding one or more plies of a ultra-high modulus carbon fiber polymer onto the elongated cylinder 20 with carbon fibers oriented in a unidirectional configuration along an axis A at a C offset of about 0° (see above for explanation of axis A, axis B, and offset C). In some embodiments, the carbon fibers can be configured as ultra-high modulus carbon fiber pre-impregnated with epoxy resin. In other embodiments, about six plies of ultra-high modulus carbon fiber pre-impregnated with epoxy resin can be applied to comprise the stiffening layer 32. In yet other embodiments, the stiffening layer can comprise a thickness of about 0.060 inches.

Next, the strengthening layer 34 can be bonded to the stiffening layer 32 by bonding one or more plies of a carbon fiber polymer onto the stiffening layer 32 with carbon fibers oriented in a unidirectional configuration along an axis A at a C offset of about 90°. The carbon fiber polymer of the strengthening layer 34 can comprise a lower modulus than that of the stiffening layer 32.

Lastly, the heat transfer layer 36 can be bonded to the strengthening layer 34 by bonding one or more plies of a carbon fiber polymer onto the strengthening layer 34 with carbon fibers oriented in a unidirectional configuration along an axis A at a C offset of about 45°. The carbon fiber polymer of the heat transfer layer 36 can be configured with a modulus to facilitate heat transfer from the elongated cylinder 20, to the stiffening layer 32, to the strengthening layer 34, through the heat transfer layer 36, and into an ambient surrounding.

The benefits and advantages of the present application include that stiffening layer 32 comprises an ultra-high modulus carbon fiber that can be up to three times stiffer than carbon fiber used in the relevant art. One benefit can be that the stiffening layer 32 comprises ultra-high modulus carbon fiber to provide a stiffer composite gun barrel with reduced vibrations upon firing. Reduced vibrations can lead to increased accuracy for single shots, increased shot-to-shot accuracy, and increased accuracy for high volume fire.

Another advantage and benefit can be that the strengthening layer 34 provides strength to the composite gun barrel 10. Added strength can increase safety for a user of the composite gun barrel 10. A benefit of the heat transfer layer 36 can be that the transfer of heat can be facilitated from the elongated cylinder 20, the stiffening layer 32, the strengthening layer 34, and the heat transfer layer 36, to ambient surroundings. Facilitated heat transfer can improve shot-to-shot accuracy, user safety, and increase composite gun barrel life. Another advantage can be that the stiffening layer 32, strengthening layer 34, and heat transfer layer 36, can function in a synergistic fashion to dampen vibrations and increase heat transfer, thereby improving composite gun barrel performance. The benefits can also include a stiffer and more accurate barrel that also dissipates heat more quickly than standard carbon barrels leading to longer barrel life and improved shot-to-shot accuracy. Other benefits include reduced weight of the composite gun barrel and increased strength of the composite gun barrel. 

I claim:
 1. A composite gun barrel coating comprising: a stiffening layer of carbon fiber polymer bonded to an elongated cylinder; wherein the stiffening layer comprises high modulus carbon fibers oriented in a first unidirectional configuration, the first unidirectional configuration oriented about parallel to a longest axis of the elongated cylinder.
 2. The coating of claim 1, wherein the carbon fibers comprises a modulus of greater than about 3,400 MPa.
 3. The coating of claim 1, wherein the carbon fibers comprise a modulus of greater than about 9,000 MPa.
 4. The coating of claim 1, wherein the stiffening layer comprises at least six plies of carbon fibers.
 5. The coating of claim 1, wherein the stiffening layer comprises a thickness of about 0.06 inches.
 6. The coating of claim 1, further comprising a strengthening layer, the strengthening layer comprising a carbon fiber polymer with carbon fibers oriented in a second unidirectional configuration, the second unidirectional configuration oriented about perpendicular to the first unidirectional configuration.
 7. The coating of claim 6, wherein the strengthening layer comprises a modulus less than a modulus of the stiffening layer.
 8. The coating of claim 1, further comprising a heat transfer layer, the heat transfer layer comprising a carbon fiber polymer with carbon fibers oriented in a third unidirectional configuration, the third unidirectional configuration oriented between about parallel and about perpendicular to the first unidirectional configuration.
 9. The coating of claim 8, wherein the heat transfer layer is configured to transfer heat from the coating.
 10. A composite gun barrel coating comprising: a stiffening layer of carbon fiber polymer comprising high modulus carbon fibers oriented in a first unidirectional configuration; a strengthening layer of carbon fiber polymer comprising carbon fibers oriented in a second unidirectional configuration, the second unidirectional configuration oriented about perpendicular to the first unidirectional configuration; and a heat transfer layer of carbon fiber polymer with carbon fibers oriented in a third unidirectional configuration, the third unidirectional configuration oriented between parallel and perpendicular to the first unidirectional configuration.
 11. The coating of claim 10, wherein the stiffening layer comprises a modulus of greater than about 9,000 MPa.
 12. The coating of claim 10, wherein the strengthening layer comprises a modulus less than a modulus of the stiffening layer.
 13. The coating of claim 10, wherein the heat transfer layer comprises a modulus less than a modulus of the stiffening layer and greater than a modulus of the strengthening layer.
 14. The coating of claim 10, wherein the stiffening layer is bonded to an elongated cylinder, the strengthening layer is bonded to the stiffening layer, and the heat transfer layer is bonded to the strengthening layer.
 15. A composite gun barrel comprising: an elongated cylinder comprising a chamber at a proximal end and a muzzle at a distal end, the elongated cylinder further comprising a bore traversing the elongated cylinder from the chamber to the muzzle; and a carbon fiber coating comprising a stiffening layer, a strengthening layer, and a heat transfer layer; wherein the stiffening layer comprises ultra-high modulus carbon fibers oriented in a first unidirectional configuration, the first unidirectional configuration oriented parallel to a longest axis of the elongated cylinder; wherein the strengthening layer comprises carbon fibers oriented in a second unidirectional configuration, the second unidirectional configuration oriented about perpendicular to the first unidirectional configuration; wherein the heat transfer layer comprises carbon fibers oriented in a third unidirectional configuration, the third unidirectional configuration oriented between parallel and perpendicular to the first unidirectional configuration.
 16. The composite gun barrel of claim 15, wherein the stiffening layer comprises a modulus greater than about 9,000 MPa.
 17. The composite gun barrel of claim 15, wherein one or more of the stiffening layer, the strengthening layer, and the heat transfer layer extends at least in part from the chamber to the muzzle.
 18. The composite gun barrel of claim 15, wherein one or more of the stiffening layer, the strengthening layer, and the heat transfer layer comprise multiple plies of carbon fiber.
 19. The composite gun barrel of claim 15, wherein one or more of the stiffening layer, the strengthening layer, and the heat transfer layer comprise multiple plies of carbon fiber configured with more plies laid at the muzzle than at the chamber.
 20. The composite gun barrel of claim 15, wherein one or more of the stiffening layer, the strengthening layer, and the heat transfer layer comprise multiple plies of carbon fiber configured with more plies laid at the chamber than at the muzzle. 